Current technology for custom shoe makers to measure the size of their customers' feet includes methods such as 3D scanner, plaster reverse mould, manual measuring and so forth. These conventional ways of measuring only collect data. Therefore, due to factors such as the differences of material, style, and manufacture crafts, a custom-made shoe can only be made after repeated attempts to measure. In addition, foot-size measuring by applying conventional methods or 3D scanning demands a high degree of skill in the operator, which considerably increases the costs of making shoes. Because of the expense involved, customized shoe making is available only as a luxury item. Moreover, 3D scanners are not portable, and thus require the customer to go to the site of the scanner to be measured. On the other hand, conventional manual measuring requires the shoe maker or other skilled professional to measure the size of their customer face to face. To solve the aforementioned problems, we provide a type of shoe-shape measurer, for which a picture is enough for a successful measurement.